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We read with interest the 2 articles just published in Circulation by Ansell1 and Granger and Armaganijan,2 which discuss, “Should newer oral anticoagulants be used as first-line agents to prevent thromboembolism in patients with atrial fibrillation and risk factors for stroke or thromboembolism?”

The discussion is relevant, because it will have a major impact on the clinical management of these patients. Although vitamin K antagonist treatment was addressed in brief by Ansell,1 we would like to emphasize the value of this treatment when appropriately managed.

The mean time in therapeutic range for vitamin K antagonist treatment in Randomized Evaluation of Long-Term Anticoagulant Therapy (RE-LY) (dabigatran etexilate), Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) (apixaban), and the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) (rivaroxaban) trials were 64%, 62%, and 55%, respectively.1,2 In a substudy to the RE-LY study, Wallentin et al3 showed no effect of dabigatran etexilate versus vitamin K antagonist treatment in patients with a time in therapeutic range >65.5%. With the use of the management modalities self-testing and, in particular, self-management, time in therapeutic range is reported to be at least 70%.4

The above-mentioned studies found a reduced number of clinical complications in terms of major thromboembolism, major bleeding, and death in favor of the new drugs. However, when self-testing and self-management are used as reference, the effect is substantially diminished, reflected as the numbers needed to treat.

The numbers needed to treat for dabigatran etexilate regarding major thromboembolism, major bleeding, and death is 172, 400, and 204, respectively. For apixaban, the numbers are 303, 105, and 238, respectively; and, for rivaroxaban, the numbers are 333, 500, and 333, respectively. If patients are managed by self-testing or self-management in comparison with conventional management, the numbers needed to treat are 185, 675, and 101, respectively.

The control groups in the above-mentioned trials are managed conventionally. If these patients instead were managed by self-testing or self-management, the potential benefit of the new drugs would most likely be reduced.

The new drugs have many obvious advantages and will be increasingly used. There are patients who, for various reasons, should be offered the new anticoagulants, although we do not know the long-term benefits of these drugs. However, vitamin K antagonist treatment still has a strong place as an anticoagulant therapy when managed optimally. Therefore, self-testing and self-management should be increasingly used as management options as alternatives to the more expensive and not yet established direct and indirect thrombin inhibitors.

Disclosures

Dr Christensen has received lecture fees from Boehringer Ingelheim, AstraZenaca, Bristol-Myers Squibb, and Pfizer. Dr Larsen has received lecture fees from Boehringer Ingelheim and Pfizer. Dr Hasenkam has received consulting fees from Roche Diagnostics, Johnson & Johnson, Edwards Lifesciences, and St. Jude Medical. The authors report no other conflicts.

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Newer oral anticoagulants should be used as first-line agents to prevent thromboembolism in patients with atrial fibrillation and risk factors for stroke or thromboembolism.
Circulation.
2012;
125:
159–
164.

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Efficacy and safety of dabigatran compared with warfarin at different levels of international normalised ratio control for stroke prevention in atrial fibrillation: an analysis of the RE-LY trial.
Lancet.
2010;
376:
75–
83.